BUG - Keyboard use: number pad 0 causes the gem count to drop, then restore
Win10
When collecting gems, using the arrow keys, I tapped the 0 on the number pad. The mission box shows the number drop by one, then restore to the correct number, without actually dropping anything.
Oh that's a funny one! I don't think that's a bug per se, but possibly an unfortunate behavior. For some reason that key is mapped as an alternate for Cargo Eject, so it does pop out a gem. However, I also just noticed that sometimes a gem will pop out too close to the player sub and instantly get picked back up. This might be what you were seeing. Please let me know if there's something more to it.